generated: '2026-09-05'
method: searched
source: openapi/seshat-markets-kronos-quant-signal-api-openapi.json
docs: https://kronos.seshat.markets/docs#x402
model: >-
  Keyless by design: x402 micropayments ARE the authentication. Paid endpoints answer HTTP
  402 with a signed payment requirement (price, USDC asset, destination, network); the
  buyer-controlled wallet signs an authorization and the client retries with the payment in
  the PAYMENT-SIGNATURE (or legacy X-PAYMENT) header. Settlement is real USDC on Solana
  mainnet (~400ms) or Base L2 (~2s) via the PayAI facilitator, using EIP-3009/Permit2 (EVM)
  or exact SVM (Solana) schemes - see /.well-known/x402 (saved in well-known/). Free
  endpoints require no credentials at all; there is no signup, no API key, and no OAuth.
summary:
  types:
  - apiKey
  api_key_in:
  - header
schemes:
- name: x402Payment
  type: apiKey
  in: header
  parameter: PAYMENT-SIGNATURE
  description: x402 v2 payment payload. Required for paid endpoints when the service manifest
    at /.well-known/x402 has enforcement=active_mainnet. Send the signed payment in this header
    (or the legacy X-PAYMENT header) to satisfy the 402 challenge.
  sources:
  - openapi/seshat-markets-kronos-quant-signal-api-openapi.json